1. Field of the Invention
The present invention relates to image processing, and more particularly, to an image processing method and apparatus, in which an image is segmented into regions and image processing is performed on each of the regions.
2. Description of the Related Art
Research on segmentation associated with digital video signal processing has steadily attracted attention. In the field of segmentation, which has become an essential part of various multimedia applications, new techniques are being applied for effective analysis and representation.
The video signal segmentation has applications in various fields and the segmentation result can be effectively used in display quality processing, video encoding, and object recognition.
In the field of display quality processing, a three-dimensional (3D) display and a 3D TV enhance a 3D effect using binocular disparity. However, as binocular disparity increases, eyes' fatigue increases and a ghost effect occurs. A main reason binocular disparity causes eyes' fatigue is that vergence-accommodation conflict arises.
Persons can feel a cubic effect because their brains reconstruct a 3D world using a monocular depth cue, such as brightness information, or a pictorial depth cue included in a two-dimensional (2D) image as well as binocular disparity. By processing the monocular depth cue well, the cubic effect can be enhanced. For example, persons feel that a bright object is closer to them than a dark object even when those objects are the same distance from them. By using this feature, the brightness of a close object is increased and the brightness of a distant object or a background is reduced, thereby improving a depth effect and a 3D effect.
There have been attempts to improve the 3D effect of a 2D image using image processing based on only a monocular depth cue without relying on binocular disparity.
U.S. Pat. No. 6,157,733 entitled “Integration of Monocular Cues to Improve Depth Perception” and U.S. Pat. No. 6,252,982 entitled “Image Processing System for Handling Depth Information” disclose techniques for extracting an object of interest from an input image and differentially processing the extracted object.
Those techniques are intended to improve a 3D effect on the assumption that segmentation has been performed or on the alternative assumption that depth estimation has been performed.
However, those conventional techniques have some problems. First, a 2D video cannot be segmented all the times. Also depth estimation from a 2D video is not always possible. For example, when a camera moves and an image contains an independently moving object, depth estimation cannot be performed on the image.
When a 3D effect is increased under inaccurate segmentation or depth estimation, degradation in display quality, such as unnatural screen display, occurs as the cost of 3D effect improvement.